The metaphorical hymen of the anus. Like the hymen, this is "broken" upon penetration to the aformentioned area, eliminating the subject's anal virginity.
So...is that behymen still intact?
by Silly Whitey November 08, 2003
An imaginary version of a woman's hymen that is inside the anus of every gay man. It is "broken" the first time he is anally penetrated.
I heard Lance Bass broke his beymen last week. Guess who broke it. Joey Fatone.
by Scoots April 13, 2003